[gemy]

Some ideas; when Harry get's there, it is often best to take both dogs out for a walk. Hopefully you have a friend, or a partner that can go with you.

Then once the walk is done, enter into your home. Harry will go second into the house after your Yorkie.

If there was any incidence of aggression on that walk, do NOT let either dog off the lead when you enter the house.

Instead walk both dogs through the house, on lead, and be prepared to correct any aggression on either dogs' part.

See how they respond to each inside the house. If all is good, then let your Yorkie off the lead, and then Harry.

Feeding time, try to feed them in the same room, but at different ends of it. Hopefully both dogs understand sit/stay and will wait for you to put down the food.

Stand between the dogs until they finish eating. One will almost always finish ahead of the other. Do NOT allow which-ever dog finishes first to go to the other dogs' dish. Use your body to block the dogs forward movement.
Do this for every meal. I always stay in the room until the dogs are finished eating. Magic my big male, is my fastest eater, garbage guts! And he will always try to advance to the next dogs' dish. Now of course a simple NO, stops him in his tracks.

Toys: I never leave toys out unattended. Toys are high value rewards here. We use them as rewards for training. In the beginning, if you want a play session with both the dogs at the same time; then you need two humans to play too; ie one on one. Throw toys in different directions. etc.
Or alternatively one dog is crated or kept in separate room when you play with a toy with the other dog.
The only exception we make is at Christmas time, when all our dogs have a new toy hanging on the tree. They each get to "open" their toy together. Have a good chew and play with it. Then what will usually happen, one dog will drop their toy, and go over to investigate the others' toy. Once this starts, toys are put away. And we open up our own gifts then.

Walking together, sleeping in the same room/house, eating together, will do a whole lot to help them bond with each other.

Good luck, and I hope all goes well.