@alnilam --3rd for Three Degree and Old Plank Roads. The reason it's called Three Degree Road is becuase it was laid out in the early days of auto travel when the engines would overheat easily. They kept the gradients gentle so the cars could make the hills without overheating. Hence the road grades are no more than about 3% with a few exceptions. Old Plank continues the same way. It will bring you into the SW end of town down the hill via Roosevelt Blvd.
If you can get to Freeport, the trail is a good way up. As Swalfoort pointed out, it brings you into town from the SE. The last four miles are not yet completed, but have been scraped down and are rideable, though slow if you're not on a mountain bike. The trail doesn't yet go all the way to Marinaro Park. You should get off the trail at Loco Lane where Burd Bros Landscaping is, onto Herman Road and into town. You'll see our sharrows.
Alternatively, you could get off the trail at Bonniebrook Road (Summit Twp municipal bldg and the road dept gravel pile), turn left onto Bonniebrook for 1/2 mile (it's a busy and unpleasnt road to ride on), then turn right at the stop sign/intersection onto Herman Road and follow it into Butler.
How you want to go really depends upon where your sister lives.
@Mick -- what JeffinPgh says. Besides, if the pie is really good, and he's burned up all those calories -- well, his stomach made him do it! And you go hungry instead. :>(