Any mistakes in my summary?

[Fazzu]

Arthur who is working as a solicitor had to go to Eel Marsh House to collect some important papers. He comes to see and hear strange things there: ‘A woman in black and the cry of a child’. Finally somehow from the papers of letters and from Mr. Daily who had lived in the town for fourteen years, Arthur comes to know about the woman who is a ghost and the child’s cry. After some weeks, Arthur married Stella. A baby boy was born to them a year later. But Stella and the baby boy died when Arthur saw the ‘woman in black’ under a big tree. On the whole, the story is a flashback Arthur telling to his four children born to Esme`.

[Tdol]

Arthur, who is working as a solicitor,
Finally, + I would move the 'somehow' part to the end of the sentence
After some weeks- you change to the past tense here- I'd use the present all the way through after starting with it.

[Fazzu]

Thanks Tdol.

Arthur, who is working as a solicitor, had to go to Eel Marsh House to collect some important papers. He comes to see and hear strange things there: ‘A woman in black and the cry of a child’. Finally, from the papers of letters and from Mr. Daily who had lived in the town for fourteen years, Arthur comes to know about the woman who is a ghost and the child’s cry somehow. After some weeks, Arthur marry Stella. A baby boy born to them a year later. But Stella and the baby boy die when Arthur see the ‘woman in black’ under a big tree. On the whole, the story is a flashback Arthur telling to his four children born to Esme`.

Am I correct now?

[Coffa]

"Arthur, who is working as a solicitor, has to go to Eel Marsh House to collect some important papers. He starts to see and hear strange things there: a woman in black and the cries of a child. Eventually, through letters and from Mr. Daily, who has lived in the town for fourteen years, Arthur somehow comes to learn about the woman, who is a ghost, and about the child's crying. After some weeks, Arthur marries Stella. A baby boy is born to them a year later. But Stella and the baby boy die when Arthur sees the ‘woman in black’ under a big tree. Altogether, the story is a flashback Arthur is telling to his four children born to Esme."

[Fazzu]

Oh thanks again Coffa.