I've been looking all over the internet with help for this specific problem, but I haven't found the answer anywhere, so I decided that this is the best place to ask. I am growing an apricot tree from seed and it has been doing very well. It is still in a pot and is a little over a foot tall but is very healthy. However, something came along and snipped off the tip of the tree where all the new growth was coming up and now my tree has stopped growing upwards! Of course, there are around 5 healthy branches that are still growing, but it's not getting any taller!
Young Fruit Tree Problem
Certified GKH Gardening Expert
Pruning is generally done during dormancy, and the leader is actually pruned down in most stone fruits.
These links have more information.