Hello. I can help. Can I get back to you in a couple hours.
Where along the length is the notch?
I would sister it with a 2x12x4'-8". From the face of wall to 2' past the end of the notch.
I would use 16d nails at 4" o.c. top and bottom
Hello. Do you have any other questions for me on this topic? If you could rate my answer, I would appreciate it.