Senior royals from around the world are gathering Tuesday for a memorial service for Prince Philip at Westminster Abbey that will incorporate hymns and other touches dropped from his funeral last year because of the pandemic.

Buckingham Palace hasn’t yet said whether Philip’s widow, Queen Elizabeth II, will attend the service of thanksgiving. The 95-year-old monarch was deeply involved in planning the event, but she has experienced unspecified mobility issues in recent weeks.

Buckingham Palace is expected to confirm on Tuesday morning whether she will attend.

Elizabeth, who recently recovered from COVID-19, didn’t go to a Commonwealth Day service at Westminster Abbey earlier this month, but she continued with other scheduled engagements, including in-person audiences.

About 1,800 family members and guests have been invited to the memorial. Only 30 people attended last year’s funeral, conducted under the strict COVID-19 lockdown rules then in place that forced the queen to sit alone wearing a black mask as she mourned the loss of her husband, who she called her rock.