In 45:8-9 we find Yosef bringing his two sons, Menashe and Efraim, to be blessed by Yaakov before he passes away. They approach Yaakov and Yaakov asks, "ויאמר מי אלה? ויאמר יוסף אל אביו בני הם" - Yaakov said Who are they? an Yosef said to his father They are my sons.
Rashi explains that Yaakov asked how he could have such descendants as Yeravam, Ahab and Yahu from Efraim and Menashe, and maybe because of these descendants they are not worthy of the blessings.
Yosef responded to Yaakov by saying "בני הם" - they are my sons.
What happens later does not matter. For better or worse they are still our children, and therefore deserving of our love - deserving of your brachos.Leave the later problems for later, do not deny them the brachos just because of things that will happen later.