2.5 yr old not eating properly?

the best option is variety when it comes to feeding children.. many different foods. She also may be excreting too much acid and what ever you are feeding her is turning into gas. you have to burp children when they eat or teach them to burp if they feel gased up. not burping when you have build up in the stomach can cause vomiting even bowel rupture from the instant change in bodily pressure.