Hey SpeedRacer7! Visiting the family?
Well, Sintra is a great place to visit, it's a small tourist town you should spend a day at.
You're probably already going to spend some time in Lisbon, so after a nice coffee around the Chiado area visit the major monuments, The Jeronimos, Belem Tower, the Castle of Sao Jorge and go to a Fado House for dinner (restaurant with live typical portuguese music) there are few of those around the Castle and at Bairro Alto.

If you're going to Nazare and Fatima I would sugest going there via the coast roads starting in Lisbon, through Guincho, Santa Cruz, Peniche until you reach Nazare.

Also, going south from Pinhal Novo, ther's Arrabida, and Setubal, for some nice shell fish lunches, and the city of Evora, another historical place.

Other than these, if you have the time and money, why not spending a couple of days in Porto the second major city or the Algarve.

I wouldn't mind serving as a guide to you in Lisbon but I'm also on vacations right now at home in the Azores islands. But if there's anything I can help, send me a PM here and I'll reply as soon as I can.

Have a great trip