"Congrats to my beautiful friend," Garth, 44, captioned a black-and-white pic of the two. "#friends #bff #baby #iloveyou @torispelling."
Spelling's rep confirmed to Us Weekly on Wednesday that the actress was expecting her fifth child with her husband, Dean McDermott. The couple — married since 2006 — are already parents of Liam, 9, Stella, 8, Hattie, 4, and Finn, 4.
Spelling and Garth have remained close since starring as Donna and Kelly Taylor, respectively, on Beverly Hills, 90210, from 1990 to 2000. They reunited on screen for the short-lived ABC comedy Mystery Girls in 2014, and their kids have even become best pals over the years.
Garth and her ex-husband, Peter Facinelli, share daughters Luca, 19, Lola, 13, and Fiona, 10. They split in March 2012 after 11 years of marriage and finalized their divorce in June 2013. Us broke the news in July 2015 that Garth had tied the knot with actor David Abrams.
"[Jennie] brings out a side of me that I need and love. I don't laugh with anyone as much as I laugh with [her]," Spelling told Us in August 2014. "When we were young, we had times where we went out and went crazy, but … we had moments where we were home knitting in sweats. I remember being at your house at night, and we would go to Michaels and pick up food and hang out. We were DIYers then!"
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