An Australian toddler drowned in a Wellington Hotel after her grandfather left her unattended in a bath, a coroner has found.

An inquest into the death of 23-month-old Leila Sofia Riquelme found she accidentally drowned after she was left alone in a filled bath at the Rydges Hotel in March 2014. Coroner Garry Evans said the case illustrated the importance of vigilance when it came to children and water.

Leila, her 4-year-old sister Nina, mother, and grandparents Jane Cookson and Fernando Riquelme were staying at the innercity hotel to attend a family wedding. The court was satisfied there was no criminal liability or suspicious circumstances.