Question:
If on Shabbos, a Kattan ties one knot on the shoes of a father and then a second Kattan ties another knot on the same shoes, so now the shoes have a double knot, was any Melacha performed? Are the shoes permissible to be worn by the father? Thank you.
Answer:
The second son that tied the second knot did the melacha, because he now created a full knot. Regarding the father, he is allowed to wear the shoes because they are usable even if they are not tied.
Best Wishes
Sources:
Maharsham 6-34, Shevet Halevi 8-173(4), Shemiras Shabbos Khilchoso 15-54.
