Recently, my social media feed was flooded with posts celebrating National Siblings Day. As I scrolled through Facebook and Instagram, I saw message after message following the same formula: a photo of someone with their brothers and/or sisters, a brief note of appreciation for those individuals, and of course the hashtag #nationalsiblingsday.

For the uninitiated, National Siblings Day was created in the 1990s by a New Yorker named Claudia Evart who had lost her brother and her sister before the age of 40. She designated April 10, her late sister’s birthday, as an annual holiday to honor all siblings—both living and deceased. While it received some recognition in the United States and Canada during the 1990s and 2000s, National Siblings Day has risen to prominence—like many lesser-known holidays—on social media.

Though I didn’t post about my own brother on April 10, the relentless stream of social media activity that day got me thinking about him, as well as my brothers-in-law and sisters-in-law. I am grateful for every one of them and I have learned much about life and faithfulness from being around them.

But my family members—both by blood and by marriage—are not the only people who have shaped me. As part of the family of believers, I am eternally grateful (pun intended) for my brothers and sisters in Christ.

In his letter to the Ephesians, the Apostle Paul writes that God the Father chose to adopt us as sons (and daughters) through Jesus Christ. In Romans, Paul describes us both as God’s children and as heirs. It’s an amazing and comforting thought: No matter what kind of earthly family you come from; you are part of God’s family in Christ!

Surprisingly, though many of my social media connections are with Christian people, I didn’t see one person post about their spiritual siblings this year on National Siblings Day. It’s understandable, and I certainly don’t judge anyone for it. Perhaps it was wise not to co-opt the holiday by changing or expanding its original meaning. Or perhaps not. I wonder if the Apostle Paul himself would have seized the opportunity to speak to an unbelieving world (or unbelieving social media followers) about being adopted into God’s family on National Siblings Day.

Regardless, we don’t need a holiday to encourage or appreciate our brothers and sisters in Christ. The first letter to the Thessalonians concludes with instructions to “build each other up” as brothers and sisters and to “acknowledge those who work hard among you, who care for you in the Lord and who admonish you.”

As you think about your church family, your brothers and sisters in Christ, which spiritual siblings are you most grateful for? Which ones have loved you, taught you, encouraged you, and shaped you? Don’t wait until next April to tell them. Call one of them today and honor them with a personal message of appreciation. No hashtag required.