PEOPLE has learned that Chris Watts has two personal effects in his Colorado jail cell: a Bible and a photo of his wife and children, his alleged victims

Chris Watts Keeps Bible & Photo of Slain Family in Cell, Source Says: 'Nothing to Do but Reflect'

Chris Watts, the Colorado father accused of murdering his pregnant wife and their two young daughters in August, has been sitting in jail for more than a month — and, according to one source with whom he has been in touch, “He has nothing to do but reflect on what happened. That’s basically it.”

Watts spends 23 hours a day in his cell at the Weld County Jail under “Close Watch Protocol,” a technical name for suicide watch. He has no TV. Once a day, he is allowed to go to the common room, where he is alone. In that room is a table with a communal newspaper that he is free to read.

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His cell is no less sparse. PEOPLE has learned that the 33-year-old has just two personal effects: a Bible and a photo of his wife and children, 34-year-old Shan’ann Watts and girls Bella, 4, and Celeste, 3 — the same people he allegedly killed.

“He doesn’t have much to do in jail,” says a source who has spoken to Chris.

Chris, who occasionally speaks with guards and can talk to other prisoners, is keeping a low profile as he awaits his eventual trial.

“He sleeps a lot,” the source says. “He can just sit there and look at the picture and read the Bible.”

Image zoom From left: Chris and Shan’ann Watts

Image zoom Shan’ann Watts (center) and her daughters

They were reported missing on Aug. 13 and their bodies were found on property belonging to Chris’ former employer Anadarko Petroleum, authorities announced not long after he was taken into custody.

Anadarko fired Chris the same day as his arrest.

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In an arrest affidavit obtained by PEOPLE, investigators revealed that they had discovered Chris’ affair with an unnamed co-worker, which he initially denied. The document also alleges that he confessed to killing Shan’ann, who was 15 weeks pregnant.

RELATED VIDEO: Pregnant Mom & 2 Daughters Killed at Home — Allegedly by Husband — Before Bodies Were Dumped

However, the affidavit states, Chris allegedly claimed he only strangled his wife after watching her kill Celeste when he told her he wanted to separate.

Image zoom From left: Chris and Shan’ann Watts Shanann Watts /Facebook

“He’s not doing well at all,” this source previously told PEOPLE. “The gravity of the situation has hit him like a ton of bricks. Depression is setting in, and he’s despondent.”

Chris has not yet entered a plea and is due to return to court in November.

His lawyer did not respond to PEOPLE’s requests for comment but, according to a statement from the state’s public defender’s office, their attorneys are barred from discussing ongoing criminal cases.

At a joint memorial service for Shan’ann and her daughters in August, she was remembered as “a woman of love,”