Sleep over

So my baby girl is 5.5 months and my parents are dying to have her sleep over. I feel like she is still too young but I want her to know her grandparents so we visit them at least once a week. She’s exclusively breastfed but I do pump once a day to allow her to drink from a bottle. She’s sleeping through the night thanks to Babywise. What are your thoughts? I’m a first time mom and staying at home (resigned from my job) so I guess I assumed she’d be with me every night for her first year of life. Anyone else’s baby has been away for a night? (Also my parents are old school and don’t believe in Babywise schedule but they did raise 5 kids so..)