May my mother use my father's priority date to adjust in the USA

If you are asking regarding 245(I) eligibility, then yes, your mother may be considered "grandfathered" under the petition your uncle filed for...

Embassy called to get visa stamped for an expired I 797

This most likely means that the Embassy will issue him a new, updated visa in the passport.

Was Interviewed in San Bernardino - passed - received oath letter - they cancelled my oath taking - transferred my docs to LA :(

The Los Angeles District Office of USCIS should issue the notice of oath taking appointment by mail. Make sure that you address is up to date.

H4 Travel duration and limit

If the visa remains valid, your wife should not have a problem remaining out of the US for 4-5 months. However, to ensure that the visa remains...

Am I Eligible for EB2 category?If not, suggest me what I need as an extra to get eligible for it.

The EB-2 category (and its subcategories) involves a highly complex set of rules and requirements. I recommend that you consult directly with a...

In Los Angeles, this is generally permissible and I do not see why it would be different in Seattle. You can find out by actually walking in to ask...

Oath taking letter... Means that my application is approved?

Yes, scheduling the oath taking means you have passed the examination. Congratulations!

H1 Extension - New I-94 date and the old I-94 expiration date has a gap?

You should not have accrued any unlawful presence if the application for extension of H-1B was filed before the previous I-94 expired and the...

What exactly does an ESTA approval under the Visa Waiver Program mean?

You may have "overstayed" but did not stay past a date certain on your I-94? Most student's are admitted in "D/S" status such that an "overstay"...

When my dad got deported they told him that the only way he can come back in US. if her sister be able to file a petition for

You need to consult with a qualified US Immigration attorney to determine whether your father could legally be readmitted to the US. This depends...