2nd child -Baby Shower - Baby Feet Theme

I am planning a baby shower for my sister, for her second child which he or she is DUE April 25th.

I am planning the shower long distance,
she live in SC, so I will probably have it Hopefully the 2nd week of March.

she did not have a shower in SC for her last baby, I had one for her in NY,
so I figured why not have one in SC for her friends there, it will be small.

my questions are:
how should I word the invite since its a baby shower for a second baby, I dont want anyone to feel obligated to buy gifts.

I know they do a shower -called
Diapers or Dinner, but this really doesnt work because the shower may be 2 months before baby is born and she cant fit a bunch of food in her freezer for that long, Right?

Also I am doing baby feet has the theme, pink and blue since she doesnt know the sex,
ANY cute ideas out there?
Please share?

I got feet cookie cutters, so I will make cookies,
and for favors I am doing blue/pink feet soap and a sponge/loofah thingy I found at target dollars spot.

If anyone knows of any other FEET stuff out there, or any ideas,
I would really appreciate it.

THANKS
Kimberly