Sprint Planning - Without Product Owner

During Sprint planning, if product owner not able to attend (due sick or emergency leave), can we still proceed with Sprint Planning? Similarly, if PO not available for Sprint Review ?

How effectively have the team collaborated with the PO in advance of these events? For example:

• Has Product Backlog refinement been performed conscientiously enough to de-risk Sprint Planning, should it happen in less than ideal circumstances?
• Have the team been reviewing work with the PO as it is completed throughout the Sprint?

The Product Owner is responsible for managing the Product Backlog, including expressing the Product Backlog Items, ordering the Product Backlog Items, and ensuring the Development Team understands the work in the Product Backlog to the level needed. Product Backlog Refinement helps support this and helps the Development Team and Product Owner collaborate to add the necessary details, identify dependencies, and order the items.

Product Backlog management and refinement is an ongoing activity. Even after a Sprint starts, whatever remains on the top of the Product Backlog should be well-refined and ordered. If the Product Owner isn't able to attend the Sprint Planning session, the Development Team should be able to determine what they can do and begin to formulate a plan for doing it.

There is some level of risk. For example, if the Product Owner has been on leave for an extended period, the Product Backlog may not be as refined as it should be. This is a risk that would have to be mitigated in some other way, such as having someone with sufficient knowledge and skills to be able to fill in for the Product Owner during extended absences. These would be organizational decisions.

During Sprint planning, if product owner not able to attend (due sick or emergency leave), can we still proceed with Sprint Planning?  Similarly, if PO not available for Sprint Review ?

@Perakam Venkata Ramesh Babu, The Scrum Guide says that the Scrum Team is self-organizing and cross functional, therefore when life happens, like the cases you mentioned, the Scrum Team should self-organize around these situations.

Here's the excerpt from the Scrum Guide.

Scrum Teams are self-organizing and cross-functional. Self-organizing teams choose how best to accomplish their work, rather than being directed by others outside the team. Cross-functional teams have all competencies needed to accomplish the work without depending on others not part of the team.

Hope that helps.