Tributes have been paid to a “lovely” woman who died suddenly at home with her young son.
Police were called to Swinburne Road in Ipswich at 17:00 GMT on Wednesday after the woman’s body was found. The child was treated at the scene but died.
The pair have been named locally as Kia Russell and her son Kamari.
A boy, 17, was arrested at the scene. The grounds for his arrest have not been disclosed, but it is understood not to be murder or manslaughter.
Lisa Horne, who lived next door until December, said news of the deaths was “really shocking”.
“She was in the garden with her son, or when we were doing the car she was there with hers. She always said ‘morning’ or ‘hello’.”
Ms Horne, who said the woman was in her late teens, added: “She never had any issues and was quiet. I just feel at a loss, at such a young age for both of them – no life at all really.”
The Reverend Mary Sokanovic, the priest in charge of the parish of Whitton with Thurleston and Akenham, said the church would be open for people to “find a quiet space or pray”.
“It’s absolutely distressing. There aren’t words for it,” she added.
She described the area as a “very mixed and varied parish”.
Suffolk Police said the next of kin had been informed, and officers have appealed for anyone with information to contact them.
The teenager is being questioned at Martlesham police station.