:salam2:
Following hadith stress some points, to not curse our children or other Muslims etc in our Dua lest they are actually accepted at that time, not sinful things, not cutting relations... etc - From Riyaad us-Saliheen
Jabir (May Allah be pleased with him) reported: The Messenger of Allah (PBUH) said, "Do not invoke curses on yourself or on your children or on your possessions lest you should happen to do it at a moment when the supplications are accepted, and your prayer might be granted.''
[Muslim].
Commentary: Almighty Allah always listens to everyone's prayer but He has fixed certain times when He grants more prayers addressed to Him. Therefore, one should never curse oneself or one's own children or one's own business, etc., lest this is done at the time when prayers are accepted by Allah and then one has to regret it all his life.
Abu Hurairah (May Allah be pleased with him) reported: The Messenger of Allah (PBUH), "The supplication of every one of you will be granted if he does not get impatient and say (for example): `I supplicated my Rubb but my prayer has not been granted'.''
[Al-Bukhari and Muslim].
The narration of Muslim is: "The supplication of a slave continues to be granted as long as he does not supplicate for a sinful thing or for something that would cut off the ties of kinship and he does not grow impatient.'' It was said: "O Messenger of Allah! What does growing impatient mean?'' He (PBUH) said, "It is one's saying: `I supplicated again and again but I do not think that my prayer will be answered.' Then he becomes frustrated (in such circumstances) and gives up supplication altogether.''
Ubadah bin As-Samit (May Allah be pleased with him) said: The Messenger of Allah (PBUH) said, "Whenever a Muslim supplicates Allah, He accepts his supplication or averts any similar kind of trouble from him until he prays for something sinful or something that may break the ties of kinship.'' Upon this someone of the Companions said: "Then we shall supplicate plenty.'' The Messenger of Allah (PBUH) said, "Allah is more plentiful (in responding).''
[At-Tirmidhi].
wasalam