In a series of snaps on her Instagram, Alyson showed how "leprechauns" had come and transformed the $8million home she shares with husband Alexis Denisof and their two children, daughters Satyana and Keeva.
Alyson's home was decorated with green streamers everywhere and a rainbow balloon arch by some lavish windows.
The Buffy the Vampire Slayer star and her children also got in on the act, with Alyson wearing an all-green ensemble, completed with a cap with a clover on top that read "Lucky."
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Her children also had on green headbands covered in clovers and novelty glasses that included leprechaun ears and hats.
The post showed off the star's lavish $8million home including a conservatory with some floor seats, beautifully deep couches, an opulent lighting fixture, all surrounded by windows which led out into her impossibly large garden.
Fans loved Alyson's lavish home
Another shot showed a dining room, with a table covered in a clover table sheet and a huge bookcase that was stacked full of books and ornaments.
"The leprechauns went crazy at our house again!" the How I Met Your Mother star captioned her post.
Fans couldn't believe their eyes with how Alyson had decorated, and they especially loved the star's home.
Alyson's children joined in on the fun
"I'm just distracted at how amazing that room with the big windows and super deep couches looks," wrote one fan. "Dream reading spot," they added.
Another fan said: "I want to grow up in your house," and a third posted: "Your house seems so pretty and warm."
Another fan praised Alyson's decorations, as they wrote: "Wow, that's a lot of green …. wouldn't be good if you all hated the colour green or something. Anyways, love the decorations, they're amazing."
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But in an adorable video, Alyson shared what happened when her daughters returned home from school, as their pooch got a lot of fusses.
"I think she missed you," the actress giggled. "That's how we all feel."
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