We started feeding Logan cereal and slowly introducing baby feeds at the end of 5 months. I was not in a hurry to start this phase but he was. He has been trying to grab food off our plates since 4 1/2 months. 
Sam is helping to feed. He is a little too helpful sometimes. He "shared" his tater to with Logan yesterday. Logan gummed it to bits and I had a mild panic attack. Oh sweeet Sam!!
I'm not sure how much went in his mouth. 
The Dr. said he needs more calories since he dropped to the 5% for weight. So when it isn't chaotic he gets cereal and baby food twice a day then I'll nurse and give him a bottle at night.