Did you cause your father's leg to break and fall short in serving him?

What happened on your part is a grave sin that necessitates promptly repenting to Allah, because serving your father in his state of incapacitation is obligatory upon you. So, continue to honor your parents and treat them kindly, and especially seek your father's رضا (pleasure/satisfaction). Do not inform him of your negligence. As for your mother's shortcoming in prayer, it is incumbent upon you to remind her of the importance of prayer in a gentle manner, without harshness.