A couple of games that havent been mentioned are:
1. Putting rice (uncooked) and small safety pins in a fairly small bowl. Then what you do is sit the person down in a chair, put the bowl that has the rice and safety pins in their lap, then have someone sit next to them holding an empty bowl. Blindfold the person holding the bowl with the rice & safety pins and the object of the game is for the person to ONLY grab the safety pins and place them in the empty bowl. You can do it for however long, but its usually only for one minute. Its not as easy as it seems, TRUST ME!
2. Grap a bigger bowl than in game #1 and put a bunch of cotton balls in along with a wooden spoon. Have the person playing put it in their lap. Then get another bowl about the same size, but make sure its light in weight. Have the person place that bowl on top of their head. Then, for a minute's time, have them close their eyes and try to scoop up the cotton balls and put it inside the other bowl thats one their head. You could have someone sit next to the person to hold the bowl steady in her lap. This game is really funny because as the person scoops up the cotton balls, they think they have a lot on their spoon when they really dont because since cotton balls are so light, they cant tell whether they are putting any in the other bowl or not!!
3. Cut pieces of paper depending on how many guests you are expecting. On two of them write "mom" and on the other two write "baby". Of course you need to crumble them up so no one knows which one have "baby" or "mom" written on them. So after you have passed all of them out, ask who got the ones that say "baby" and "mom". Then, ask the "moms" to choose their partner ( it has to be a person who got "baby". After the partners are chosen, you will have two teams. One with mom and baby and the other with the other mom and baby. Have the moms sit in a chair and the babies sit on the mom's lap. Then give them a small baby bottle filled with coke and see who drinks it first! This game can be played the same way, but instead of bottles of coke, you can do jars of baby food. This one is actually funnier.
4. Another game could be to put several baby items on a tray, like a pacifer, bib, diaper, etc. and pass it around quickly just enough for everyone to get a glance at it. Then, have everyone write down what they remember seeing on the tray. The ones that has the most correct wins!
Hopefully now you have an idea of some games!

I think having a theme is a good idea! If i think of a cute one i'll let you know, but the fairy one is really cute!!
Have fun!