If a child who is not yet the age of chinuch (still 4 years old) is playing with a muktseh toy
a) Are we obligated to take it away from him or can he continue to play with it?
b) Are we allowed to touch the muktseh toy in order to take it away and/or move it from his reach so that he does not continue to play with it?
Please send sources/rationale
1) The Magen Avraham (343), whose ruling is cited by the Shulchan Aruch Ha-Rav and by the Mishnah Berurah, rules that chinuch for children with regard to prohibitions begins from the age that the child understands the concept of something that is forbidden. I have seen quoted (in the name of Rav Moshe Sternbuch, and in the name of Rav Elyashiv zt”l) that the age is 5-6, but some write that it can be earlier (3-4).
It is certainly good to start chinuch in these matters from a young age, so that the child grows up with the knowledge that some things are not done on Shabbos.
2) The muktzeh toy should not be moved in a regular manner for this purpose, but moved irregularly, preferably with the back of the hand, or with the body. It should not be moved in the normal way because this is not a “use” of the item, and one does not require its “space”.
If it is a keli shemelachto le-issur, and some use can be made of it, it can be moved for the purpose of the use that can be made of it.