Sure ... you can purchase OS X Server from the App store for $20 and it will set up a Time Machine Server on your Mac Mini which will reliably service your MacbookPro and any other Mac computers you have using Time Machine already included of OS X. All computers need to be on the same network, and using WiFi is fine, although the first backup session will be lengthy. Subsequent hourly backups will usually be less than a minute or so depending on new file content created.
I use a 2011 Mini as a HTPC, and it also shares iTunes music and movies to all household computers and AppleTVs, as well as providing 12TB of backup storage for all the computers and notebooks in the house. It also has a few TB of "shared" file/library/archive storage.
There are other features of Server which you might eventually find a use for as well.