Fahan Mura Cross The 7th century Celtic interlace cross from the Fahan churchyard in County Donegal, Ireland, is thought to be one of the earliest versions of the famous Celtic sun cross designs in Ireland. On the opposite side of the cross is the only Greek inscription found from early Christian Ireland reading "Glory and honour to the Father, Son and Holy Spirit". A monastery was founded here by St. Colmcille in the 7th century which survived for 500 years.
Each family member gets a celtic knot. You can burn them into wood, stamp, emboss or embroider them to label belongings, rooms, etc. When a child gets engaged, give their spouse an individual knot that can be combined together with the other.