The actress popped up in Alpharetta, GA Monday -- about 40 minutes outside of Atlanta -- where she and her husband, Bader Shammas, were on a nice little walk with their baby boy, Luai, who was chillin' in his stroller ... with dad taking care of push duties, as LiLo snacked.

If you're wondering what the heck Lindsay and co. are doing in the southern state right now -- you might be happy to hear it's likely work-related ... namely, a new Netflix movie.

She was recently announced to star in yet another Christmas flick opposite Kristin Chenoweth -- this after having been in a different Xmas movie for them a couple years back, 'Falling for Christmas.'

Seems the streamer liked her stuff and signed her up for another one! BTW, we recently got Kristin at LAX ... and she had some kind words for Lindsay -- saying she's a pleasure to work with.

Seeing how films/shows are constantly filming in the state of Georgia -- and with 'Our Little Secret' already in production -- it's a safe bet that's exactly what LiLo's shooting right now. Lucky for her, she's got her family right by her side ... which seems to be her new norm.

It's interesting ... Lindsay normally lives abroad in Dubai, but lately -- she's been here in America for business. Like we said up top ... she was just in the Big Apple a couple weeks ago for the premiere of the new 'Mean Girls' ... in which she had a brief cameo/appearance.