How do I tell a physician that I think my mom may be being poisoned by my dad?

Hi. I am very concerned for my mother. One day my mom was just fine then out of the blue from one second tot he next she became very ill very fast. Later on in the day I went to pick up my daughter from there & she was barfing every 10 minutes. No joke. My daughter told me earlier in the day as my mom has her face in the toilet she yelled to my dad (he was in the other room) she thought he should take her to the hospital. According to my daughter she heard my dad yell back "You should have thought of that before....." That's all she overheard. I basically had to threaten my dad to take her to the hospital. Well she needed to be there cuz she was there for 9 nts. She'd been out of the hospital for a few weeks. Then as she's waking up my dad prepared malt-o-meal. My mother takes one bite & it all happens all over again. She's back in the hospital & they don't know what's wrong. My parents hardly get along anymore. My uncle has expressed concern like me. What's weird is that he said the same thing that I was thinking. I hardly speak to my uncle we live on separate sides of the state of Texas. We may speak to him once or twice every 2 years or so. I know I shouldn't accuse anyone of anything like that. that is a very strong accusation to make against someone but I just got a weird feeling that won't go away. Maybe I watch too much Tru TV. Any advice would be most appreciated. Thanks.