Question: When did Beorhtweald, Ealdorman Of Kent's mother die?

Knowledge 1: Beorhtweald, Ealdorman of Kent
Beorhtweald Ealdorman of Kent was an English ruler of the 9th century AD.His father was Burgred of Mercia, his mother: Æthelswith, and his brother: Beorhtnoð æthling of Kent. [SEP] Knowledge 2: Æthelswith
Æthelswith (c. 838–888) was the only known daughter of King Æthelwulf of Wessex.She became Queen Æthelswith when she married King Burgred of Mercia in 853.The couple had no issue.Her marriage probably signalled the subordination of Burgred to his father-in-law and the Saxon kingdom at a time when both Wessex and Mercia were suffering Danish (Viking) raids.Burgred also had ongoing problems with the Kingdom of Powys on his western border and in 853 Æthelwulf subjugated the Welsh state on Burgred's behalf.Repeated Danish incursions over the years gradually weakened Mercia militarily and in 868 Burgred was forced to call upon Æthelswith's brother King Æthelred of Wessex to assist him in confronting an entrenched Danish army at Nottingham.This was the last time the Saxons came to the aid of the Mercians and is also notable as the occasion on which Alfred the Great, another brother of Æthelswith's, married his Mercian wife Ealhswith.Burgred's reign lasted till 874 when the Vikings drove him from the kingdom and he fled to Rome with Æthelswith.He died shortly after.Æthelswith lived on in Italy, to be buried at Pavia in 888.
Knowledge 1: Beorhtweald, Ealdorman of Kent
Beorhtweald Ealdorman of Kent was an English ruler of the 9th century AD.His father was Burgred of Mercia, his mother: Æthelswith, and his brother: Beorhtnoð æthling of Kent. [SEP] Knowledge 2: Beorhtnoð æthling of Kent
Beorhtnoð æthling of Kent was an English ruler of the 9- 10th century AD.His father was Burgred of Mercia; his mother, Æthelswith, and his brother, Beorhtweald Ealdorman of Kent.
Knowledge 1: Æthelswith
Æthelswith (c. 838–888) was the only known daughter of King Æthelwulf of Wessex.She became Queen Æthelswith when she married King Burgred of Mercia in 853.The couple had no issue.Her marriage probably signalled the subordination of Burgred to his father-in-law and the Saxon kingdom at a time when both Wessex and Mercia were suffering Danish (Viking) raids.Burgred also had ongoing problems with the Kingdom of Powys on his western border and in 853 Æthelwulf subjugated the Welsh state on Burgred's behalf.Repeated Danish incursions over the years gradually weakened Mercia militarily and in 868 Burgred was forced to call upon Æthelswith's brother King Æthelred of Wessex to assist him in confronting an entrenched Danish army at Nottingham.This was the last time the Saxons came to the aid of the Mercians and is also notable as the occasion on which Alfred the Great, another brother of Æthelswith's, married his Mercian wife Ealhswith.Burgred's reign lasted till 874 when the Vikings drove him from the kingdom and he fled to Rome with Æthelswith.He died shortly after.Æthelswith lived on in Italy, to be buried at Pavia in 888. [SEP] Knowledge 2: Beorhtnoð æthling of Kent
Beorhtnoð æthling of Kent was an English ruler of the 9- 10th century AD.His father was Burgred of Mercia; his mother, Æthelswith, and his brother, Beorhtweald Ealdorman of Kent.

Answer: 888