no its not enough social interaction.
Well if your thinking he may think the food is poison, hmmm, maybe buy/ make him a disk of music he likes, make him a scrapbook full of photos he would like?
I only say these things as a gentle way of showing you care.
Have you explained to your older son how much his brother looks up to him and how you would appreciate his help?
I hope things are going okay
Xxxxx