How to deal with a dog that gets possessive over the owner

I got a message from a friend of mine Heather today. HI Roddy. We've had an incident this morning that I was hoping to nip in the bud immediately and I wondered if you may have some advice? Our dog is lovely... but his breed is known for being a bit dominant. We were prepared for that and I am pretty sure that I am pack leader in the house. He has basic obedience, isn't allowed on the couch, and is crated when we're out or at night. However, it seems that while he doesn't resource guard food or toys at all... he is starting to resource guard me. And he isn't happy to share attention with the kids. Not an issue with my eldest, but he's been showing "jealousy" with the youngest two and this morning snipped at my middle daughter when she hugged me while he trying to get attention. This is obviously WAY not OK Basically I am not sure how best to proceed and haven't been able to find some definitive answers online. I do realise now that the dog is absolutely an affection/attention seeker. He gets right up in your business when he wants to be petted or loved or validated. Basically, the kids going back to school has presented a situation where we are alone together for much of the day right as he's hit his teenage stage and it's given him the wrong idea and I've inadvertently reinforced it. I intend to dial this back completely because I suspect this may be driving some of this. So that's on me. I also suspect that we need to work more on his "place" training and have him be doing a lot more duration and obedience work. He isn't very food driven but is motivated by praise so this may help him feel valued at times when he is not able to demand affection. However, where I'm failing is how to establish the pecking order a bit better in my home... how do I let him know that the kids come before him? Do I have the kids feed him? Help with the obedience training? #bepackleader #roddykirk #bpl #dogwhisperer #balancedtraining #balanceddogtraining #balanceddogtrainer #realdogtraining #lifechanging #positivedogtraining #dogsofinstagram #abdt