Transcript for Family wonders if daughter's death is due to tainted alcohol

Next tonight here, the new warning from the state department today and a family speaking out to us tonight after their daughter died drowning in a pool at a Mexico resort. Her parents now want to know, was the alcohol tainted? Here's ABC's gio Benitez. Reporter: Tonight, the state department issuing an urgent warning over tainted or substandard alcohol in Mexico, and this family from Wisconsin believes their adult children could have consumed it just six months ago. 20-year-old abbey conner and her 23-year-old brother Austin, were found unconscious floating facedown in a five-star resort's pool. Bey had a broken collarbone and later died. Bit and decided let's celebrate with a drink, so we go up to the bar and another group that was already there start talking. Reporter: So people you didn't know. Reporter: They say they haven't interviewed the bar ternd or other guests and there's no surveillance video. Their blood alcohol level is said to have been a .25, and Austin can't remember how many shots he had. Is it possible you drank too much? I have thought about it, and it is a possibility, but how if we're in a group of people, do two people at the same exact time just pass out in the pool and no one sees it? Reporter: The iberostar resort saying "The Milwaukee journal sentinel" we only purchase sealed bottles that satisfy all standards required, and saying, we are deeply saddened, and reiterate our deep et cetera sympathies to the family. They say they have no record of tainted alcohol, but now the family plans op filing a lawsuit. Gio Benitez, thank you. When we come back here, a man shot and killed by police.

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