expression, suru verb (irregular)
treasure as a family heirloom; cherish forever
Hyperbolic expression of gratitude, often said upon receiving a gift. Literally 'to make it a family treasure', implying deep appreciation and intention to keep it forever.
こんな素敵なプレゼント、家宝にします！
I'll treasure this wonderful gift as a family heirloom!
いただいた絵は家宝にさせていただきます。
I will cherish the painting you gave me forever.