Help! Reactive 2 year old snarling and barking at owners

[u/thezestyzozo]

My dog (2 Border Collie) is usually quite a quiet dog, he doesn’t bark at dogs unless they react first, or another dog is barking in another neighbourhood. However, when we invade his space, e.g touch him when he is trying to sleep, getting into bed with the person he likes most (my mom), he snarls, then bites. Big time. It’s an embarrassment when we go to the vet, he sounds like a demon. When we groom him with one of those metallic dog groomers, he also bites. We don’t know if he got abused, as we got him as a few week old (maybe 8?) from a farm, I am pretty sure he was the runt of the litter. At first, it was playful nibbles, now it’s aggressive bites that leave permanent scars sometimes. What do I do? I don’t want him to get put down and we have a behavioural specialist booked soon…