Aliyah Warren is still trying to piece together how her “big sister” ended up in handcuffs in a Boston courtroom to answer for a murder charge. The last time Warren saw Nora Nelson, the 24 ...

Nora Nelson — or “Andi,” as Warren knew her growing up — was charged with murder on Feb. 6, in connection with the death of Joseph Donohue, 65, of Charlestown.