Latest on this…
If at first you don’t succeed (in getting what you want) pester, pester and pester again.
So if your mum isn’t throwing the tree you’ve brought her, just carry on bumping it into her until she does. And if she’s with a friend, drop the tree in front of both of them, wait until they walk past it, then pick it up and run between them, catching both of them on the backs of their knees, before dropping it in front of them and repeating.
Another key point in the success of the above is to choose a tree of substantial length. A minimum of 4 feet, and preferably longer.
Twice now he’s tried to pick up a suitable branch which is still attached to the living tree!!
And unfortunately am reinforcing all the time as he has such a despondent look in his eyes if you don’t throw the stick, so I can’t refuse him!!