Sibling tenants in a duplex - one is great, the other not so much

[Arthur McCormack]

Fellow BP members,

Reaching out to ask if some of you have experienced a similar situation, that I'm about to deal with, before and how you may have handled it or, in hindsight, might have handled it differently than you did? Or if you have thoughts on the matter?

Backdrop: About 1.5 years ago rented the larger of two units to couple with one child; they passed the background checks and for the first 6 months paid on time, no issues. During this time, the smaller unit came up for rent and tenant referred sister. She passed background checks and even offered to pay $50 more a month than what I was asking, as they are close (as a family) and wanted to live next to each other. Long story short, the leases are coming up for renewal in 2 mo - the sister has been great, pays rent in advance and online, she even paid to have the who interior repainted by pro painter and  keeps the place in good shape. The brother and wife next door however... they had one more child over the past year (seems wife was already in first stages of pregnancy but did not disclose on application) - nothing against kids, but there have started to be plumbing issues and come to find among some pre-existing issue with buried pipes, they're also clogged with baby wipes; they pay late, and are not keeping up with the property upkeep as outlined in lease. 

Today: I'm very inclined to non-renew the brother's lease, my concern is the sister may decide to bail too, that would leave me with two vacancies at the same time. Sure  - dealing with vacancies is part of being a landlord, but have any of you had a sibling/tenant scenario like this that you were able to navigate successfully? My thoughts are to speak with the sister and lay it out straight to her, that she is a good tenant and I'd like her to stay. What are your thoughts on the matter?

P.S. even though leases started at different times, I made them short initially so renewals would line up with end of school/start of summer.