[Sister Havana]

Just doing a google search I found this information:

Pi Kappa Phi does it.
- Alumni Initiation - Pi Kappa Phi Fraternity allows brothers to initiate men who have already attended an accredited institution. Men invite their grandfathers, fathers and brothers to take part in initiation. Alumni initiates are full members of Pi Kappa Phi and have the same rights as men initiated in college. The only restriction is they cannot previously be a member of any national social fraternity and they must be completed with their schooling. They can be members of honor fraternities and/or service fraternities.

So does Delta Upsilon:
Delta Upsilon's Alumni Initiate Program provides a perfect opportunity to introduce non-affiliated men to the vision and values that have guided our Fraternity for over 165 years. Many represent the qualities and talents we look for in chapter advisors. In many cases they may be recruited to serve the colony as valuable, confident, and knowledgeable resources.

It sounds like Delta Chi does too (I read an article about fathers of guys in one chapter becoming alumni initiates of that chapter.) As do Theta Xi and Phi Sigma Kappa, but I haven't seen any specifics about those groups.