Why are you so sure that Laura and the Bush girls were in favor of abortion? I never heard that anywhere........They are devoutly religious and go to church regularly in Dallas from what I hear.
I saw the interviews on TV sometime during the last 4 years. Laura "Arbusto" and the 2 daughters "Arbusto" are firmly rooted in the pro-abortion camp. I seem to recall their sympathies are also extended to the homosexual special rights cause.
MacNaughton already answered your question - here is Laura Bush in her own words with Larry King:
http://www.youtube.com/watch?v=HtNabdDx_mU
Barbara Bush was a big Planned Parenthood supporter but had to suppress that when GHB became POTUS.
Laura is a Methodist, and that church has been leading the way with PCUSA and ECUSA to transform Christianity into a shadow of its former self...more tolerance...less Jesus.
Just cuz Laura and the girls go to church, that has nothing to do with being a Christian.