The trial of a teenage cheerleader accused of murdering her baby and burying her in the backyard has been shown photos of her posing with a huge baby bump at prom two days before she gave birth.

Brooke Skylar Richardson, now 20, is on trial in Lebanon, Ohio, for allegedly murdering her baby in May 2017 then burying her in her backyard.

Skylar, as she is known, was 18 at the time and had told no one she was pregnant, including the baby's teenage father who she'd had a brief fling with. She says the baby was a stillborn and that she delivered her in the middle of the night on the toilet while her parents were asleep.

Prosecutors however say she killed the baby then set fire to her tiny corpse to try to conceal that she had given birth.

She was arrested in July after confessing to a gynecologist that she'd had the baby - who she called Annabelle - and buried her in her backyard.

Prosecutors rested their case against her on Monday with a video taped confession where she described taking a lighter to the baby's foot.

Skylar's defense team started presenting their case on Tuesday.

The jury was shown several photographs of Skylar throughout her adolescence which documented her drastic weight fluctuation. They were also shown photographs of her with Brandon Saylor, her boyfriend in 2017, when she gave birth.

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Skylar Richardson is pictured on May 5, two days before she gave birth, with her then boyfriend Brandon Saylor before they went to prom. She had a full baby bump but no one realized she was pregnant - though she had been told by doctors that she was - because her weight fluctuated so much

Brooke 'Skylar' Richardson is pictured yesterday during her murder trial in Lebanon, Ohio

Skylar and Brandon are pictured in March 2017, around six weeks before she gave birth, during a Spring Break trip. He was not the baby's father and began dating her when she was already pregnant

Brandon was not the baby's father; he was Trey Johnson, a different teenager who Skylar had a fling with in the summer of 2016.

She and Brandon began dating long after she conceived the baby.

In March 2017, Skylar and Brandon were photographed in the ocean during a Spring Break trip to Florida.

She posed in the ocean in a bikini and at the time was nearly full term but no one suspected she was pregnant.

She did not have it confirmed until April 26, during a visit to the gynecologist.

In February 2017, the teenager picked out a bright red, sparkly prom dress. The jury was shown a photograph of her trying on the dress that month and then again, on prom night, on May 5, two days before she gave birth.

Her belly was much more pronounced in the second picture.

In the hours after the birth, Skylar texted her boyfriend saying: 'I'll tell you about it later but last night was like the worst ever and I didn't go to sleep till 5.30 but I feel sooooo much better this morning I'm happy.'

Richardson, pictured in the courtroom yesterday, is on trial in Lebanon, Ohio, for allegedly murdering her baby in May 2017 then burying her in her backyard

The defense showed photos of Skylar in February, 2017, when she selected her prom dress (left) and in the same dress two days before she had the baby (right) with a more noticeable bump. They said the fact she was able to get into it proved that her weight gain was not substantial and that the baby was small, likely affected by intrauterine growth restriction. Prosecutors said it was corseted and she could have loosened it

The 20-year-old is on trial for murder, manslaughter and gross abuse of a corpse in Ohio

They called her father, Scott, to the stand and he described how shocked he was to learn not only that his daughter had been pregnant but that she had given birth in secret.

He described his daughter's history of anorexia and weight fluctuation.

He said that because her weight went up and down so frequently, they did not think it was odd when she grew larger as a result of pregnancy.

Richardson said he wished his daughter had been honest with him and his wife about her baby and that they would have taken it into the family.

'We were in shock. We didn't know she was pregnant, we had struggled with an eating disorder...

'We would have taken [the baby] into the family. I think we would have been in shock and we probably would have been angry but...' he said.

At the end of his testimony, Scott stifled tears as he told the jury: 'She would never hurt another living being let alone a baby.'

He also said he was never aware that his wife, Kim, had been encouraging her to lose weight and that the biggest regret of his life was not having an attorney present when Skylar made the 'confession' that she had set fire to the baby, a claim he and the defense says was a lie and was coerced.

Kim did not testify on Tuesday.

Her husband said that she had been subpoenaed by the prosecution so was not allowed to sit in the courtroom but had been going to court every day.

As part of their defense, Skylar's attorneys showed photos of how her weight fluctuated before she became pregnant (above) within the space of six months. She'd suffered from anorexia for years beforehand, her family says, and was under pressure from her mother to stay slim

A photo that the defense presented on Tuesday shows Skylar before she conceived after gaining weight

Skylar's father Scott (shown arriving at court with her on September 6) testified that she would 'never hurt another person'. Her mother Kim, left, did not testify. Cameras did not show him while he was on the stand, per his request and has been the case with most of the trial witnesses

Brooke Skylar Richardson is shown in during her second police interview last July where she told police she set fire to her baby

Prosecutors showed the jury this photograph of the infant's skeletal remains after they were dug up from the family's yard

Brooke Skylar Richardson took this selfie hours after giving birth after going to the gym

They also showed texts between Skylar and her mother before the baby was born about her losing weight.

Doctors sent Skylar's mother an email, saying she was pregnant, but she insisted it was a mistake.

Skylar wrote: 'I meant like I figured it was probably just a mistake your scaring me. Please still have a good day mommy im (sic) sorry if u (sic) r (sic) stressed now but i wouldnt (sic) be getting smaller if i (sic) was and i (sic) wouldnt (sic) be on birth control i (sic) love u (sic) plz (sic) dont (sic) be mad at me or sad it was just an accident please lets (sic) have a good day its prom week.

Her mom replied: 'I cannot tell you how my heart stopped because I care too much and want I (sic) to have a future. That eliminates all that. I will I just a (few) hours to adjust whew whew.'

Ten days after giving birth, Skylar text her mother and told her she had lost 20lbs.

She said she announced it in one of her classes and her everyone clapped.

'I could cry, u (sic) literally [are] my hero,' the mother said.

Trey, the baby's father, told police that he and Skylar 'did stuff' for around a week in July and August in 2016 but that she suddenly blocked him on social media afterwards.

A doctor who is an expert in still births also testified for the defense to stand up Skylar's claim that the baby was stillborn.

He said that among other things which makes him believe her, she described the condition of a stillborn during her first police interview, without prompt and without having any medical knowledge.

He believes the baby suffered intrauterine growth restriction which is a common cause of stillbirth.

The fact that Skylar weighed more when she conceived the baby than she did after within days of delivery supports his statement.

He also said that her history of eating disorder, malnutrition and the fact that she was not taking any type of prenatal vitamins means the baby's chances of survival were less than in other women.

The way she described how it 'plopped' out of her, with no umbilical chord attached, are also signs of a stillbirth, he said.

Prosecutors say the fact she continued to take birth control pills despite being told she was pregnant in April 2017 proves she wanted to get rid of the baby.

But Skylar insisted she had no idea they could harm the unborn infant and that because she had been prescribed them, she thought they were safe to take.

A major question in the case which remains unanswered is why she was prescribed the pills if she was pregnant.

More than one doctor has however testified for the defense that taking birth control pills so late on in the pregnancy, the third trimester, would not have had an effect on the baby.

The trial continues in Lebanon, Ohio, on Wednesday with more witness testimony for the defense.

It remains unclear if Skylar will take the stand.