Copy rows of data based on alpha condition

Hello,
I have a summary worksheet that houses all records. I'd like to break that summary worksheet into in multiple worksheets grouped by last name, but still maintain my summary sheet for updating. I'd like to update one worksheet but have those updates transfer to the other worksheets.

I have a summary worksheet that stores information like lastname, first name, birthdate, email address & contact information. I'd like to take that information and pull it into another worksheet grouped by last name (worksheet 2 A-H, worksheet 3 I-P, worksheet 4 Q-Z)