I failed my baby šŸ˜­

I need advice. I feel so stuck. My husband and I adopted a 1 year old lab about 6 years ago. One of our main reasons for even buying a house was so heā€™d have a yard. Last year he ā€œattackedā€ my son for climbing on his back. He didnā€™t bite him but he growled and all that and scratch the shit out of my sons face. The cat constantly attacks him from behind so we thought it was along those lines. We also sought a dog trainer and tried to associate getting meat and treats whenever the baby was around. We also put him in daycare because we are not able to keep with with what he needs physically. Heā€™s locked behind a gate majority of the day now (because I just canā€™t chance it again) he can still hear us and I go and pet him but I feel so guilty. Iā€™ve been letting him around my son only while I am supervising and for short times. Heā€™s been doing ok until today. My son is a toddler now and was not being nice to him (he wasnā€™t even touching him) which of course he needs to learn to be nice) (but that lesson shouldnā€™t come with scratches or an ER visit) and he showed his teeth šŸ˜© I feel like itā€™s inevitable that theyā€™re around each other at some point without me there and all it takes is one time. Iā€™m just so sad. What are your thoughts??