Involuntary manslaughter and child endangerment in Texas?

HELP!!! My grandson drowned(we think) in a bathtub. Reason we think is that there are some things that makes many think he may have died before he went under water(less than 2 inches deep). His heart had stopped in less than the 30 seconds he was under. Anyway my daughter has been arrested "based on statements made" and charged with manslaughter, abandon/endanger child and 3 drug charges for meds found that were her fiance's for a back injury. We have never dealt with the judicial system before but have had 4 attorneys visit her and say the case is complicated by the fact that she is totally innocent. Can anyone help me know what we can expect. This is really scary.