The phrase
"such beautiful memories" is an idiomatic expression that means memories of a past event or experience are fondly remembered and considered to be very pleasant.
Full definition
Just love the photo of you and sweet P looking out a the «chicken» — such a beautiful memory!!
After the baby is born - aaaah,
such beautiful memories.
Such beautiful memories and gorgeous scenery for your mom and you to enjoy together.
I'm glad Layla has
such beautiful memories of her grandfather.
He was amazing and I'm so grateful he was mine and that he gave
me such a beautiful memory.