We got Milo and Bella from the same litter and it was actually a god send.They had always been super close,always together and inseperable,which is why we simply could not part them and we *had* to get them both
At night they never cried and their transition was super smoothe because they had each other,but having two also means that itīs double the work..especially when it comes to potty training

They distracted each other continuously and being as they were always playing,charging around the room,and cahsing each other,even when one did want to use the pad,the other would come up behind and pounce,causing "spillage" or he/she would even get peed on! lol.Leaving them alone together is also not as great as it seems..they get into tons of mischeif and I sometimes come home to a HUGE mess

I love them both to death and we are going to get another (you can never have to many yorkies!),but NEVER asume that adding another puppy will make things easier lol

It may make nights easier,but adding a new puppy can also cause the one who was already there to regress..kind of like when you bring a baby home to itīs older sibbling.The pup that was there first can have quite a hard time..jelousy etc.Either way,they DO eventually come around and every yorkie is a blessing