Do our dead relatives watch over us?

(Al-Kafi, volume 3, page 231)

عنه، عن محمد بن سنان، عن إسحاق بن عمار قال: قلت لأبي الحسن الأول (عليه السلام): يزور المؤمن أهله؟ فقال: نعم، فقلت: في كم؟ قال: على قدر فضائلهم منهم من يزور في كل يوم ومنهم من يزور في كل يومين ومنهم من يزور في كل ثلاثة أيام، قال: ثم رأيت في مجرى كلامهأنه يقول: أدناهم منزلة يزور كل جمعة قال: قلت: في أي ساعة؟ قال عند زوال الشمس ومثل ذلك، قال: قلت: في أي صورة؟ قال: في صورةالعصفور أو أصغر من ذلك فيبعث الله تعالى معه ملكا فيراه ما يسره ويستر عنه ما يكره فيرى ما يسره ويرجع إلى قرة عين.

“Narrated from him, from Muhammad ibn Sinan, from Ishaq ibn Ammar: 

‘I asked Abi al-Hasan [al-Kadhim]: 

Does the deceased believer visit his family? 

He [the Imam] said: Yes

So I said: in which days? 

He [the Imam] said: Depending on their virtues; some visit everyday, some visit every two days, some visit every three days. 

The narrator then said: I saw in the course of his [i.e, the Imam’s speech] that he’s saying that ‘the lowest of them [i.e, believers] in status visits his family every Friday. 

I [narrator] asked: In which hour? 

He [the Imam] said: When the sun sets and such like that.

I [narrator] asked: In what image [do they visit]?

He [the Imam] said: In the image of a bird or something smaller - with which Allah sends an angel who shows him what will please him, and hides what will sadden him. And he [the dead believer] returns to his grave with comfort of the eye [i.e, pleasure].”